23572021 has 4 divisors (see below), whose sum is σ = 25714944. Its totient is φ = 21429100.

The previous prime is 23572001. The next prime is 23572039. The reversal of 23572021 is 12027532.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 23572021 - 2⁷ = 23571893 is a prime.

It is a super-3 number, since 3×23572021³ (a number of 23 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23571983 and 23572001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23572001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1071445 + ... + 1071466.

It is an arithmetic number, because the mean of its divisors is an integer number (6428736).

Almost surely, 2^23572021 is an apocalyptic number.

It is an amenable number.

23572021 is a deficient number, since it is larger than the sum of its proper divisors (2142923).

23572021 is a wasteful number, since it uses less digits than its factorization.

23572021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2142922.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 23572021 is about 4855.1025735817. The cubic root of 23572021 is about 286.7250297310.

Adding to 23572021 its reverse (12027532), we get a palindrome (35599553).

The spelling of 23572021 in words is "twenty-three million, five hundred seventy-two thousand, twenty-one".